The role of TRPV1 in the CD4+ T cell-mediated inflammatory response of allergic rhinitis.

Transient receptor potential vanilloid 1 (TRPV1), which has been identified as a molecular target for the activation of sensory neurons by various painful stimuli, was reported to regulate the signaling and activation of CD4+ T cells. However, the role of TRPV1 in CD4+ T cell in allergic rhinitis remains poorly understood. In this study, TRPV1 expression was localized in CD4+ T cells. Both knockout and chemical inhibition of TRPV1 suppressed Th2/Th17 cytokine production in CD4 T cells and Jurkat T cells, respectively, and can suppress T cell receptor signaling pathways including NF-κB, MAP kinase, and NFAT. In TRPV1 knockout allergic rhinitis (AR) mice, eosinophil infiltration, Th2/Th17 cytokines in the nasal mucosa, and total and ova-specific IgE levels in serum decreased, compared with wild-type AR mice. The TRPV1 antagonists, BCTC or theobromine, showed similar inhibitory immunologic effects on AR mice models. In addition, the number of TRPV1+/CD4+ inflammatory cells increased in the nasal mucosa of patients with AR, compared with that of control subjects. Thus, TRPV1 activation on CD4+ T cells is involved in T cell receptor signaling, and it could be a novel therapeutic target in AR.